A security alert was sparked at Westminster after a peer received hate mail containing white powder.
The message, received by Lord Ahmed, contained racist abuse - but because of the suspicious powder, a security operation was launched which led to parts of the parliamentary estate being closed.
Lord Ahmed said that he was concerned about the incident, particularly following the killing of Labour MP Jo Cox in June.
The non-affiliated former Labour peer opened the "hate mail with some frightening stuff inside" in his office at Westminster.
"Hate mail, I have had before, but this had some white powder. At first I didn't realise how serious it could be, so I threw it in the bin and washed my hands and shook off all the powder," he said.
But then he realised the potential threat posed by the message and drew it to the attention of the parliamentary security staff.
Lord Ahmed then went to the peers' terrace overlooking the Thames when he was called by security staff who told him not to move while specialist police units investigated to see if the powder was "chemical or biological material".
He told the Press Association: "Thank God it was okay and all I can say is thank you to all the fantastic staff and Black Rod's team who acted so swiftly.
"What happened to my colleague Jo Cox, one needs to be aware that these type of things can happen."
A Lords spokesman said: "Peers car park and parts of the terrace were closed temporarily, but have now been reopened.
"The closure was put in place while a package containing a white powder was investigated by specialist police units, which is standard procedure.
"The powder was found to be non-harmful."
A Metropolitan Police spokesman said: "Police were called at 12.30pm to reports of a suspicious package delivered to the Houses of Parliament.
"The contents have been deemed non-suspicious and there are no reports of any injuries."